1. Field of the Invention
The present inventions are directed to medical devices for ambulatory care and more particularly ergonomic crutches.
2. Relevant Technology
A crutch is generally thought of as a medical device that is used to support all or part of a patient's body weight. A crutch has traditionally been made of wood or metal, and is ordinarily long enough to reach from a patient's underarm to the walking surface. There is typically a concave surface fitting underneath the arm, and a cross bar for the hand, both used for supporting the body weight. Crutches may be used by a patient for only a few days or, in some instances, a lifetime. Crutches have caused or led indirectly to multiple injuries and disorders despite their ability to transfer weight. In addition, each repetition of an injurious action can produce micro-trauma to the tissues and joints of the body. Although the human body has enormous self-repair abilities, continued exposure to such activities can outweigh these abilities, which then results in injury.
The injuries resulting from crutch use are in part due to the fact that patients overly rely upon the underarm portion to support the body weight. Most crutch designs have not taken into consideration the appropriate contour of the axilla. This has resulted in nerve injuries varying from neuropraxia to complete paralysis of the arm. In addition, the hand grip is rarely contoured to fit a patient's palm. The general construction and design of crutch hand grips does not provide the correct ergonomic orientation between the wrist and forearm even though padding may be present. Failure to achieve correct alignment and padding in the palmar area can result in disorders of wear and tear, including overuse syndromes, repetitive strain injuries, musculoskeletal injuries, and compressive neuropathies. Common injuries resulting in such usage include: carpal tunnel syndrome, wrist tendonitis, medial or lateral elbow epicondylitis, and rotator cuff muscle strains and tears. These disorders appear to be more common in the chronic crutch user, and are the result of repeated stresses on a particular musculoskeletal area.
Crutches have traditionally imported a fixed-length frame having a concave cushioned upper end for placement under the arm, a horizontally-directed rigid handle that extends between two bows that act primarily to carry the weight of a patient, and a lower end configured to contact the ground. Shock absorbing devices have been placed on crutches to lessen the impact to a patient as the body weight is transferred to the walking surface. An added benefit of a shock absorbing device is to assist a patient on uneven ground, as well. Different crutch ends have been designed to provide contact between the crutch and the walking surface. However, an appropriate gripping surface to decrease friction is necessary to prevent the crutch from sliding or slipping. A distal end that not only grips the surface but angulates with the movement of the crutch is necessary to assure full contact.
While various modifications have been attempted, there presently does not exist a crutch that incorporates the appropriate ergonomic structure in a light-weight, sure gripping, user friendly, shock absorbing, and collapsible format.